(CNN) -- South Africans gathered at a stadium Saturday for the funeral service of a woman considered the mother of the nation's liberation struggle.

Albertina Sisulu, 92, died at her home last week.

Crowds gathered at a football stadium in Soweto for the service, which follows a week of national mourning.

Flags were flown at half mast in the nation and its overseas consulates during the mourning period.

"One of the most steadfast, dignified and disciplined pillars of our struggle has fallen," said South African President Jacob Zuma, who attended the funeral. "An era has ended."

Sisulu was married to anti-apartheid leader Walter Sisulu, who was imprisoned for decades with former South African President Nelson Mandela.

In his book, "Long Walk to Freedom," Mandela says the couple's home was "a mecca for activists" during the fight against apartheid.

"It was a warm (and) welcoming place," he says, and describes her as having "a wise and wonderful presence."

But the woman affectionately called "Ma Sisulu" was also an icon in her own right.

She helped nurture a new generation of leaders in between detention periods that included a 1963 seizure by the apartheid government that led to a solitary confinement for weeks South African officials said,

Sisulu would take to the streets as soon as she was freed to rally against the trials of anti-apartheid movement leaders, the ruling African National Congress said in a statement.

After her husband was sentenced to life imprisonment in 1964, she was banned from attending gatherings of more than two people and taking part in political activities, the ruling party said.

In the 1960s, she faced various bans, including one confining her to her home at nights, weekends and public holidays, according to the party.

Despite the setbacks, she continued with her quest for liberation.

"Although politics has given me a rough life, there is absolutely nothing I regret about what I have done and what has happened to me and my family," she has said. "Instead, I have been strengthened and feel more of a woman than I would otherwise have felt if my life was different."

Zuma described the diminutive woman as a "pillar of strength not only for her family, but also the entire liberation" movement.

"She reared, counseled, nursed and educated most of the leaders and founders of the democratic South Africa," the president said in a statement.

Sisulu founded the Federation of South African Women and other civic organizations.